Solution to a weird Plesk problem – A Case Study

Recently we faced an unusual problem with Plesk Panel in a Windows Dedicated server of a customer. Whenever we clicked on Mail server settings in Plesk admin panel, it threw errors. The event viewer displayed the error as C structured exception: 0xc0000005. While running the plesk repair from reconfigurator.exe, it too threw the following error

Unexpected error
at Unable to generate dump file(internalDumpMiniDump line 745)
Execute file name: C:Program Files (x86)ParallelsPleskadminbinreconfigurator.exe

I figured out that the error only occured when the Plesk Mail Server was attempted to be repaired. If I de-selected that option, the reconfigurator.exe ran fine. So, I now knew that it was the Mail server that was the culprit. I dug deeper into the Event Logs to find out more information. I found a few more error logs in the Event Viewer.

Error 1:

Faulting application name: reconfigurator.exe, version: 12.0.18.34141, time stamp: 0x543526ca
Faulting module name: OLEAUT32.dll, version: 6.1.7600.16872, time stamp: 0x4e5873c1
Exception code: 0xc0000005
Fault offset: 0x00004660
Faulting process id: 0x1890
Faulting application start time: 0x01cfe46d8f5685fe
Faulting application path: C:Program Files (x86)ParallelsPleskadminbinreconfigurator.exe
Faulting module path: C:Windowssyswow64OLEAUT32.dll
Report Id: d1323c1a-5060-11e4-8dc6-002590aeaee4

Error 2:

Application: reconfigurator.exe
Framework Version: v4.0.30319
Description: The process was terminated due to an unhandled exception.
Exception Info: System.AccessViolationException
Stack:
at MailProviderProxy.MailProviderProxy.setDNSServers(System.String[])
at reconfigurator.CheckMailServer.Run()
at reconfigurator.SystemChecks.executeTask(reconfigurator.IPleskCheck)
at reconfigurator.SystemChecks.executeTasks()
at reconfigurator.SystemChecks.check_Click(System.Object, System.EventArgs)

I then remembered we had modified the MAIL_PROVIDERW_DLL value to smartermailproviderw.dll when we had setup Plesk and Smartermail in the server. This setting was done according to a suggestion in Plesk KB to resolve issue with Smartermail integration in Plesk 11.5. I went to the directory where the smartermailproviderw.dll file is stored. I found that there was another dll present with the name smartermailprovider.dll. I checked the versions of both the DLL files and found that while smartermailproviderw.dll was of 11.5, smartermailprovider.dll had the version 12.0.18. I immediately knew that this is the right file which should be called by Plesk service. I then modified the registry entry to replace smartermailproviderw.dll with smartermailprovider.dll. Then I restarted the Plesk services and voila! the issue got resolved. Now, I can access the Mail Server settings from the Plesk panel and also the Reconfigurator.exe no longer crashes.